A miniaturized printed rectenna for wireless RF energy harvesting around 2.45 GHz

• Published in: International journal of electronics and communications Vol. 127; p. 153478
• Main Authors: Koohestani, Mohsen, Tissier, Jérôme, Latrach, Mohamed
• Format: Journal Article
• Language: English
• Published: Elsevier GmbH 01.12.2020; Elsevier
• Subjects: Compact design; Engineering Sciences; Power conversion efficiency; Rectenna; Symmetric CPW-fed; Wireless energy harvesting; Symmetric CPW-fed; Compact design; Wireless energy harvesting; Power conversion efficiency; Rectenna; RF Energy
• ISSN: 1434-8411; 1618-0399
• DOI: 10.1016/j.aeue.2020.153478

This paper presents the design of a highly compact printed rectenna for ambient RF energy harvesting around 2.45 GHz. Its antenna structure comprises a rectangular patch with two etched U-shaped slots fed by a symmetric 50 Ω coplanar line. In spite of compact size, it has been directly integrated with a rectifying circuit on the same substrate only at the expense of a 15% frequency shift. The proposed rectenna overall dimension is only 24.9 × 8.6 × 1.6 mm3, the smallest so far reported with comparable performance, which can be easily integrated with any device for energizing low-power wireless sensor networks. It was fabricated and experimentally characterized, achieving a reasonable agreement with the expected simulated results. Measured results indicate that, at the resonant frequency, the antenna part of the proposed rectenna provides a good matching level (<−25 dB) and has a 0.8 dBi peak gain as well as nearly symmetrical radiation properties (in both E- and H-planes). The measured RF-to-DC conversion efficiency (DC output voltage) of the proposed rectenna at a low incident power of −20 dBm is about 20% (97 mV) with a load resistance of 4.7 kΩ. A demonstration experiment of a LED driven by the rectenna was also presented.